Pneumatic fastener driving machine



Aug. 29, 1961 E. J. ANSTEZTT 2,997,713

PNEUMATIC FASTENER DRIVING MACHINE Filed Oct. :0, 1958 5 Sheets-Sheet 1 jg 50d Aug. 29, 1961 Filed OCt. 50. 1958 E. J. ANSTETT PNEUMATIC FASTENER DRIVING MACHINE 5 Sheets-Sheet 2 Aug. 29, 1961 E. J. ANSTETT 2,997,713

PNEUMATIC FASTENER DRIVING MACHINE Filed Oct. 30, 1958 5 Sheets-Sheet 3 FEB F1157 Aug. 29, 1961 E. J. ANSTETT PNEUMATIC FASTENER DRIVING MACHINE 5 Sheets-Sheet 4 Filed Oct. 30, 1958 Aug. 29, 19.61 E. J. ANSTETT 2,997,713 PNEUMATIC FASTENER DRIVING MACHINE Filed Oct. 50, 1958 5 Sheets-Sheet 5 ire tats This invention relates to a machine for driving nails, staples and similar types of driven type fasteners and more particularly to such a machine operated with air pressure.

Many air operated drivers for staples and brads which have a piston, drive the fastener with a single blow. Short fasteners are not particularly subject to bending and buckling during a short driving stroke. However, difficulty has been experienced when longer fasteners are attempted to be driven with a single blow. The present machine is so constructed that it may easily drive any fastener regardless of its length or its tendency to buckle under driving forces which might be experienced in former machines. Much longer fasteners can be successfully driven and can be driven at rates commensurate with commercial feasibility. The present machine is also particularly adapted to drive the fasteners into hard wood and other similarly difficult material to penetrate.

The principal object of this invention is to provide a new and improved pneumatic driver for driventype fasteners.

Another object is to provide a light-weight, portable machine with structure preventing operator fatigue.

Another object is to provide a pneumatically operated driver for nails and the like, having a structure which avoids shock of the driving force from reaching the frame of the machine.

Another object is to provide a novel foot structure permitting automatic nail driving upon contact of the machine with material into which the nail is to be driven.

Another object is to provide a machine of character described having cooperating parts of low cost which may be assembled and disassembled without the use of tools.

A further object is to provide a machine of the character described having a one-piece plastic molded main frame having therein a nail magazine formed in a novel manner.

A still further object of the invention is to provide a new and improved machine of the character described adaptable to hand operation or semi-automatic operation, and provided further with structure for easily and accurately mounting the machine in desired location for driving fasteners.

Other objects, features and advantages of the present invention will be apparent from the following description of a preferred embodiment of the invention illustrated in the accompanying drawings, in which:

FIGURE 1 is a side elevational view of a machine embodying the present invention;

FIGURE 2 is aside elevational View of the opposite side of the machine illustrated in FIGURE 1;

FIGURE 3 is an enlarged, partly broken away and partly in section elevational view of the pneumatically operated portion of the machine of this invention, taken as indicated in part by line 3-3 in FIGURE 4 centrally through the machine;

FIGURE 4 is a sectional view taken through the machine substantially along line 4-4 in FIGURE 3;

FIGURE 5 in a view similar to FIGURE 4 taken substantially along line 55 in FIGURE 3;

FIGURE 6 is an elevational sectional view of the machine taken substantially along line 6-6 in FIGURE 3;

FIGURE 7 is a fragmentary front elevational view of the lower front end of the machine;

FIGURE 8 is a vertical fragmentary sectional View taken approximately along line 8-8 in FIGURE 3;

FIGURE 9 is a horizontal fragmentary sectional view substantially along line 99 in FIGURE 3, taken through the nail supporting rail;

FIGURE 10 is a vertical fragmentary sectional view along line Ill-10 in FIGURE 9;

FIGURE 11 is a front elevational View partly in section having the front plate of the foot member removed therefrom and taken substantially along line 1111 in FIGURE 12;

FIGURE -l2 is a horizontal sectional view similar to FIGURE 9 taken at a slightly lower level and substantially along line 12l12 in FIGURE 3;

FIGURE =13 is a perspective view of a portion of a stick of nails which may be driven in the apparatus;

FIGURE 14 is a central sectional view through a modified foot structure taken substantially along line 14- 14 in FIGURE 16;

FIGURE 15 is a sectional View through line 15--15 in FIGURE 14; 7

FIGURE 1 6 is an elevational sectional view substantially along line 16-16 in FIGURE '14;

FIGURE 17 is a view similar to FIGURE 14 of another form of foot structure;

FIGURE 18 is a view similar to FIGURE 16 and taken substantially along 1818 in FIGURE 17;

FIGURE -19 is similar to FIGURES l4 and 17 of a further modification of foot structure; and

FIGURE 20 is a sectional view of the structure in FIGURE 19 taken substantially along line 2tl'20 therein.

The machine of the present invention is intended to drive nails, one at a time, from a supply in the magazine of the machine. The invention is concerned with the construction and arrangement of parts of the machine by which each fastener is in turn driven from the magazine into material over which the driving mechanism is placed. Referring particularly to FIGURES 1 and 2, the machine has a handle 13 which may be grasped by the hand of an operator in order to maneuver the machine into proper location. The handle is integrally moloded with the main frame of the machine which may be most conveniently formed of plastic. The machine embodies a magazine portion 14 which extends longitudinally and has a lower portion or surface 15 which is adapted to sit upon the work into which the fastener is to be driven. At the front of the magazine section 14 there is mounted a barrel portion 16 for receiving the lower part of the driving mechanism. Extending above the barrel portion 16 is a cylinder 17 which contains the actual driving mechanism for forcing the nails out of the machine and into the material upon which the machine may be placed. In general, the magazine is a straight member in which a stick of nails similar to those shown in FIGURE 13, may be placed for being fed forwardly to the driving position. At the front of the magazine, there is located a metal driving guide plate structure 18 through which each of the nails is driven. Referring particularly to FIGURE '13, it will be noted that the nails have a shank portion 19 and an off-set head 20 by which they are hung on a rail in the magazine. Each nail is severed from the stick of nails and driven through the guide plate structure 18 out of the machine and into the material below.

The frame as mentioned above is preferably molded of nylon or similar plastic and is given a ribbed structure for strength. In FIGURE 1, the faces 21 of the magazine are surrounded by a raised ribbed structure 22 and openings 23 are formed in the faces by plugs in the mold. The opposite side of the frame shown in FIGURE 2 has similar faces 24 surrounded by raised ribbed structure 25 and an upper longitudinally extending channel 26 with openings 27 therein. The openings 23 and 27 are in staggered relation lengthwise of the frame in order that the 2,997,7 13 r v w plugs in the mold which form the openings might col- I lectively form a longitudinally extending channel. As particularly noted in FIGURE 8, the form of the frame is such that a central downwardly open channel 28 has an enlarged laterally extending part 29 at its upper end. The enlarged part 29 was formed by plugs in the mold which were withdrawn through the openings 23 and 27. The right hand part of the enlargement 29 is intended to receive a metal U-shaped rail 30, as seen best in FIG- URES 3, 6 and 8. This rail provides support for the nails. The rail extends for the length of the magazine, as may be seen in FIGURES 3 and 9 and is riveted in place by rivets 30a. The frame is reinforced immediately above the rail by an upstanding rib structure 31 which is joined to the handle 13 of the frame. As previously mentioned, the front portion of the frame has a barrel portion 16 integrally formed with the magazine and particularly joined to a laterally extending enlarged part 33 (FIGS. 9 and 12) molded to the front of the magazine structure.

The frame of the machine is formed of plastic giving a total weight quite easy to handle. Total weight of a typical machine is about 4 /2 pounds without nails. The bottom 15 is spaced from the nail holding rail a sufficient distance to house two inch nails and the near side of the frame as viewed in FIGURE 1 is shorter than the far side so that the ends of the nail shanks 19 are visible. Round openings in the sides of the frame additionally lighten the frame and are generally located centrally of the faces 21 and 24 between the raised reinforcing ribs. The upper rib 31 is of ventilated construction and is joined with the handle which has a central web 13a and top and bottom flanges 13b and 130. The magazine is sufficiently long to receive a relatively long stick of nails, the number depending upon the thickness of the material from which the nails are formed. The magazine on the illustrated machine is about 15 inches long from the plate guide member 18 to the opposite rear end.

The nails are supplied in stick from, as illustrated in FIGURE 13, and each nail is driven in a nail guide structure 18 in the front of the magazine. The nail guide structure is a composite, permanently assembled group of plates so formed as to make a groove through which the nail driving member will move and through which a fastener to be driven will pass during the driving thereof. The structure of the assembly may best be seen in FIG- URES 3 and 9 through 12. Referring first to FIGURE 3, the front plate 34 is rectangular, having a pair of openings therein for receiving the retaining pins to be described. A pair of side plates 35 are spaced sufiiciently far apart, forming the lateral edges of a groove 36 through which the nail driver will pass. The rearward-most plate 37 has a groove shaped more like that of the nails or fasteners shown in FIGURE 13. These plates are all riveted together as by a plurality of rivets 38 shown in FIGURE 10. The assembly is a composite intended to remain as a unit, once manufactured.

The guide plate structure 18 is located relative to the machine so that the fasteners 'will pass through the slot in the inner part and abut the front plate in the groove in position to be driven. The upper edge portion 39 of the assembly is intended to fit within a groove formed in the plastic frame of the machine, specifically the lower end of the barrel '16. A pair of guide pins 40 embedded in the plastic receive bores formed in the plates and thus locate the assembly during its installation on the machine. The actual holding of the plate assembly to the plastic machine is accomplished by a sleeve 41 having rearward finger portions 42 and 43 intended to extend around the enlargements 33 on the frame. This sleeve tightly embraces and encloses the plate assembly 18, holding it to the plastic frame, the sleeve being assembled by sliding it endwise over the plate assembly and frame enlargement. The sleeve is also provided with openings to receive a pair of pins 44 and 45. These pins have enlarged knurled outer finger grip areas 46 and 47 and each has a spring wire such as 48 shown in FIGURE 12 so that once installed by longitudinal movement into the aligned bores or openings, the pins frictionally stay in place. Once the pins 44 and impale the embracing sleeve 41 over the plate structure 18 and the end of the frame, the fasteners will be fed into proper position for driving one-by-one.

The nails are urged forwardly in the magazine by a pusher member 51. As seen in FIGURE 6, the member has a lower horizontal leg 52 which passes under the lower edge 53 of the frame so as to connect with a plate 54 riding in the nail slot. The plate 54 has an upper flange 55 so that it is formed similarly to the shape of the nail shown in FIGURE 13. The pusher may be removed from the open rear end of the magazine so that nails may be inserted. An elastic rope-like member 56 is attached to the pusher, passes over a pulley wheel 57 on the frame and extends rearwardly to an apertured plate 58 adapted to hook on to a hook 59 secured to the frame. The elastic rope maintains a forward urging of the pusher in the nail magazine. Manual release of the elastic rope will permit removal of the pusher slidingly from the magazine channel.

The driving mechanism of the present machine is intended to drive the nails by rapid repeated blows of a piston hammer structure. The hammer is driven by air and operates through a very short stroke at a rate of the order of 4500 strokes per minute. Each blow delivered is quite light when compared with a carpenters hammer blow or the blow delivered by previous single stroke pneumatic machines. The rapidity of the blows serves to drive the nails and the mechanism is equipped to follow the driving action so as constantly to be in position to properly strike the nail.

The driving mechanism is contained within the front barrel portion 16 and the cylinder 17, previously mentioned. Referring particularly to FIGURES 35, the cylinder 17 contains a carrier 60 having spaced O-rings 61 and 62 sealing the carrier slidably to the interior of the cylinder. The cylinder provides a smooth circular cylindrical barrel in which the carrier may move. Air is admitted to the space between these O-rings through a passage 63 Within an air valve 64. The source of the air is through line 65 attached to the valve. The valve 64 is attached to the cylinder 17 and positioned to be engaged by the upper end of a push rod 68, hand operated by a finger piece 69 mounted for vertical movement at the front of the handle 13. The cylinder 17 is equipped with diametrically arranged pin members 70 for cooperating with bayonet type slots 71 (FIGS. 1 and 2) in the barrel 16 to permit removal of the cylinder from the barrel by a twist to release the lock followed by longitudinal separation of the cylinder from the barrel. A thumb piece 66 about the push rod 68 may be lowered against a coil compression spring 67 to disengage itself from the lower end of the valve to permit the twisting of the cylinder relative to the barrel. The thumb piece may be held in its lowered position by any desirable catch arrangement, that shown involving a pin 72 and cooperating groove 73 on the thumb piece cooperatively locking the same in lowered position upon turning the thumb piece with the groove opposite the pin. The spring 67 also urges the trigger to its lower position by acting on the push rod as shown.

Air is admitted to the interior of the cylinder 17 whenever the valve 64 is opened. The air so admitted is trapped between the seals 61 and 62 on the carrier 60. Radial openings 74 lead the air from the outer periphery of the carrier toward the interior. A flutter type valve ring 75 controls passages through a sleeve member 76 which connects with opposite ends of the sleeve barrel part 77. In FIGURE 4, passages 78 pass through the sleeve member to the upper interior of the barrel 77 above the piston 79. Passages 80 have vertically extending passages extending through the upper enlarged part of the sleeve member 76 and down through the plastic body of the carrier to exit into the barrel 77 through openings 81 below the piston. The valve ring is round and the part of the sleeve member upon which it seats slightly obrotund so that the ring may rapidly flutter back and forth covering first one and then the other of said passages 78 and 80. The result is alternate rapid connection of opposite ends of the cylinder formed by the sleeve 77 with the source of air under pressure. The change in such connection is affected immediately upon exhaust of the particular side of the piston to which air is being conducted. The exhaust occurs as quickly as the piston moves sufficiently far to uncover exhaust passages such as '82 on the downward stroke and 83 on the upward stroke. The plastic housing of the carrier about the central barrel part 77 has vertical passages such as 84 and 85 (FIGS. 3 and which open to the bottom thereof so that exhausted air may find its way through vent openings 86 to atmosphere.

Immediately above the fluted valve ring 75 is a circular fiat washer 87 having a central opening 88 through which a part of the air admitted to the interior of the sleeve 77 may pass through the head of the carrier and through a small opening 89 in the top thereof to a position within the cylinder 17 above the carrier. This air will, of course, be at the same pressure as the air used to reciprocate the piston 79. As the nail is driven, the entire carrier moves downwardly within the cylinder 17 under the influence of the air above the carrier. This body of air also forms a cushion between the frame of the machine and the driving mechanism effectively, absorbing practically all impact or reaction of the driving mechanism which would otherwise probably be against the frame of the machine. As a result, the operator holding the machine by the handle 13 receives practically no reaction due to the driving. There is a slight amount of vibration but no jolt or jar from the driving. The air above the carrier may bleed to atmosphere through a bleed opening 90 in the top of the cylinder 17. The openings 88, $9 and 90 are so proportioned that the body of air to lower the carrier is supplied through openings 88 and 89 faster than the same may bleed out through opening 90 thus holding the carrier in place during the driving. The body of air may thereafter bleed out during upward return of the carrier under action of the spring -95.

The driving blade 91 has an upper enlarged cylindrically shaped weighted portion 92 slidable into the open lower end of the sleeve 77. The driver rests upon a rubber cushion 93 at its lower end and the assembly is maintained by a cup shaped metal retainer 94 through which the driving blade extends. The retainer slides on the outer end of the sleeve 77 and the relatively heavy coil spring 95 bears upwardly on the retainer and upon the bottom cushion 96 Within the barrel 16 to keep the blade in place and to return the carrier to its uppermost position. In the uppermost position shown, the lower end SW of the blade is in the nail or fastener receiving slot of the front guide structure 1 8.

The reciprocation of the piston 79 is such as to allow it to strike the weighted end of the driver quite rapidly. The driving of a fastener is quite rapid under these circumstances. The admission of air into the driving mechanism may be accomplished by manual operation of the trigger 69 or by contact of the mechanism with the material into which the fastener is to be driven. Referring to FIGURES l and 2, a foot mechanism $8 forms the exposed portion at the driving end of the machine. This foot as shown in FIGURES 6 through 12, comprises a split sleeve base S9 having opposite side outwardly dimpled portions 1% for the purpose of receiving side plates such as 191. As noted in FIGURES 1 and 2, plates 101 have lower work engaging points d 102 to hold the machine against travel relative to the work when subject to the vibration of fastener driving.

Referring to FIGURES 14 through 20, the basic split sleeve structure is used in all the different side plate foot structures. The sleeve has rear generally parallel fingers 103 with elongated slots 104 therein in alignment with similarly shaped slots 105 in the front wall. These slots permit limited vertical movement of the foot relative to the machine and the supporting pins 44 and 45 which pass through the slots. Upper rearwardly extending and notched ears 106 are provided on the split sleeve for the purpose of engaging a forked pushing link 107 which has an upper portion for insertion into a slot in the trigger, and lower bifurcated portions 108 for engaging the notches in the ears. By this link, the raising of the foot can also open the valve to admit air. The air valve spring 67 alone is sufficiently strong to insure the return of the foot structure to its lowermost position. The use of the link 107 to operate the driver upon work contact is effective in any desired nailing position since the spring 67 is sufiiciently strong to handle the weight of all the parts such as might be encountered in overhead nailing. In FIGURES 14, 15 and 16, a foot with side plates 109, elongated in plan and joined at the front by center notched pin 110, provides a wider foot than that shown in FIGURES l and 2. In FIGURES 17 and 18, the side plates 111 have a particular shaped lower opening notch 112 to receive a molding of similar shape, thus positioning the machine thereon. Once the machine with such a foot is properly located on the molding, the driven fastener from the machine will be properly located. In FIGURES l9 and 20 the side plates 113 are so shaped as to provide about 20 angle with the plate sleeve 99. This provides the usual angle at which a carpenter drives nails. Various foot structures may be attached as side plates to the basic sleeve and readily applied to the machine. Locating studs may be formed on the nail guide structure or the foot as desired.

The structure of the present machine is particularly equipped for mounting the same with other machines on a jig or fixture. For this purpose, the upper mounting stud 114 attached to the top of the cylinder 17 is located on the center line of the fastener to be driven. This stud can receive a handle or can be used to mount the machine on a jig or other support. When so mounted, the machine will be accurately positioned and can drive fasteners upon the lowering of the machine with the 1g.

It has been found that the machine operates equally well on air ranging in pressure from 40 to 100 pounds per inch. Lower pressures result in a somewhat slower driving rate but still satisfactory. The plastic parts are capable of quite long life and will withstand considerable abuse. In the event of damage to any of the parts, they may simply be removed from the apparatus without use of tools and replaced by a similar part quite inexpensively.

One of the features of the present machine is the ease of replacement of any part which may become damaged for any reason. The entire working mechanism of the machine may be disassembled without the use of tools. The foot structure and nail guide are separate elements easily removed. The carrier and its driving mechanism can easily be taken out of the cylinder and replaced. The air valve structure is a simple one involving a simple cone-shaped enlargement 115' held closed by the pressure of air in the line leading to it. All parts of the machine being readily separable without tools may be most easily replaced when worn. The removal of the pins 44 and 45 allows the foot structure to slide off the machine quite easily. The retaining embracing sleeve 41 then may be pulled in the direction of removal of the foot structure to remove the sleeve 41 from the assembly. The fit is tight enough to require a pull on the sleeve but not so tight as to require tools for its removal.

The nail guide member will practically fall off once the sleeve is removed. The cylinder may be removed by turning the pins 70 in the bayonet slots 71 and lifting it out of the barrel 16. The entire carrier 60 will slide out of the cylinder quite easily. Upper and lower parts of the carrier are threaded together and readily come apart. The driver 92 and piston '79 both slide freely out of the lower end of the cylinder sleeve 77. Any part that is damaged or worn may be readily replaced and the assembly or disassembly accomplished quite quickly.

The foregoing detailed description has been given for clearness of understanding only and no unnecessary limitations should be understood therefrom, for some modifications will be obvious to those skilled in the art.

I claim:

1. In a pneumatic driver for driven type fasteners, a frame having means for holding a fastener in position to be driven; a cylinder in the frame; a carrier slidable in the cylinder and a fastener driving member movable by the carrier to follow driven advancement of the fastener; a reciprocating hammer within said carrier for providing fastener driving blows to the fastener while the carrier advances to maintain the hammer in said driving relation; an air supply valve on the carrier for directing air to opposite ends of the carrier alternately for reciprocating the hammer; said cylinder providing an air chamber therein with said carrier forming a movable wall of said chamber and means for bleeding a portion of said air from within said carrier into said air chamber to advance the carrier and cushion said frame against vibration of the driving blows.

2. A pneumatic driver for driven type fasteners, comprising: a frame for holding a fastener in position to be driven; a pneumatic cylinder having a piston carrier member slidable longitudinally therein with a driving blade positioned over the fastener, said piston carrier having an upper hollow portion and a lower hollow portion secured together, each portion of the piston carrier having a piston sealing ring for sliding sealing engagement within said cylinder, said piston carrier having an air passage from its exterior to its interior intermediate said piston sealing rings, a flutter valve clamped between said piston carrier portions in position to receive air admitted through said air passage; a reciprocating hammer slidably mounted within the piston carrier member for delivering rapidly successive blows to the blade as the piston carrier member advances in the cylinder during fastener driving; said piston carrier having means for delivering air from said flutter valve to opposite ends of said hammer to drive the hammer and having means for admitting air from said valve into the cylinder for moving the piston carrier member therein and cushioning the driver frame against shock of said hammer reciprocations.

3. A pneumatic driver as specified in claim 2, in which the cylinder is removably positioned in alignment with the center of the fastener to be driven and is provided with an external mounting rod for securing the driver mechanism to a support, said mounting rod being arranged on said center to aid in locating the driver relative to desired driven fastener location.

4. A pneumatic driver as specified in claim 2, wherein the frame has a metal nail guide for the fastener to be driven including a pair of plates providing a driving slot between them for guiding the fastener and driving blade, said holder being pressed against the adjacent driver frame portion and removably held thereon.

5. A pneumatic driver for driven type fasteners, comprising: a frame having a magazine for successively supplying fasteners to a position for driving and a cylinder surmounting the driving position; a piston carrier member slidable within the cylinder and a driving blade mounted in the carrier member; a reciprocating hammer within the carrier member adapted to deliver rapidly successive blows to the blade for driving said positioned fastener; said piston carrier having passages for admitting air into the interior thereof and a flutter valve for conducting a portion of the air to the hammer, said piston carrier member having a passage for conducting the balance of the air into the cylinder for advancing the piston carrier member and blade to follow the fastener during driving and to maintain the blade in contact with said fastener, said air in the cylinder providing a cushion preventing impacts of the driving from reaching the frame.

6. A pneumatic driver as specified in claim 5 in which the cylinder is provided with a lateral air inlet and the piston carrier member has spaced seals in sliding contact with the cylinder with an air inlet to the interior of the piston carrier member therebetween, said piston carrier member being relieved between said seals to provide an annular air space about the piston carrier member.

7. A pneumatic driver as specified in claim 5 wherein the cylinder is formed with diametrically opposite fasteners and the frame has coacting fasteners permitting removable attaching of the cylinder to the frame and said cylinder carries an air valve controlling admission of air to the cylinder and said frame has trigger means for operable alignment with said air valve.

8. A pneumatic driver for driven type fasteners, comprising: a frame having means for holding a fastener in position to be driven and a barrel portion over said position; a driver including an enlarged head in said barrel portion and having a blade for contacting the fastener; a cylinder removably secured to the barrel portion and carrying a piston carrier contacting the driver; spring means in the barrel portion urging the driver toward said carrier and away from the fastener, said driver and carrier having interfitting alignment retaining portions; an air valve on the side of said cylinder for admitting air thereinto, said carrier having spaced piston seals for confining the admitted air to a predetermined space in the cylinder intermediate the ends of said carrier and passages for conducting said air to the interior of the carrier; and a hammer slidably mounted within the carrier for striking the driver to drive said fastener, said carrier having a fiutter valve and air passages for admitting air for reciprocating the hammer to deliver successive blows to the driver in rapid succession and an air passage from said valve to the interior of the cylinder beyond said carrier for supplying air to advance the carrier in said cylinder.

9. A pneumatic driver as specified in claim 8 wherein a cup shaped member is resiliently urged against the end of the piston carrier by said spring means in said barrel and said driver blade extends through an opening in the bottom of the cup and through a resilient pad between the driver head and cup bottom said driver, cup and piston carrier being capable of disassembly by relative movement alone upon removal of the cylinder from the frame.

10. A pneumatic driver as specified in claim 8 wherein the frame includes a nail magazine having a substantially straight rail for suspending nails therein by their heads, said frame being integrally molded of plastic material about the rail and being downwardly open from the driving position to its opposite end.

11. A pneumatic driver for driven type fasteners, comprising: a frame having a generally straight magazine for the fasteners and a barrel portion at one end thereof for receiving driving mechanism, said frame being integrally molded with a continuous open slot extending lengthwise of the magazine and an inner enlarged portion for receiving a rail for heads of the fasteners; a guide plate member at the front of the magazine positioned to receive a fastener from the magazine and hold the same in position to be driven; a pneumatic piston carrier mounted above said guide plate member; a driving member for contacting said positioned fastener and a hammer reciprocally carried by said carrier for striking the driving member successive blows to drive the fastener.

12. A pneumatic driver as specified in claim 11 in which said barrel portion supports a cylinder secured to the barrel portion of the frame by bayonet slots and detent fasteners permitting removal thereof without tools and said guide plate member is held in position relative to the magazine and barrel portion by demoun-table fasteners requiring no tools for removal from the driver.

13. A driver as specified in claim 11 wherein the frame magazine has lateral openings aligned with the inner enlarged portion of the open slot, each side of the frame having a plurality of said openings spaced apart and alternately arranged in non overlapping lateral alignment with the openings on the opposite frame side providing the frame with a molded one-piece magazine having said enlarged portion.

14. A driver as specified in claim 11 wherein said guide plate member abuts the front portion of the magazine and an assembling sleeve embraces said plate member and forward portion of the magazine to hold the plate member in position, said sleeve being removable by sliding motion thereof relative to said frame.

15. A driver as specified in claim 11 in which the magazine slot has a rail to support fasteners hanging therein by their heads and a pusher member with a plate portion riding in the slot also hanging on the nail, said pusher member having a portion outside the slot supporting spring means for connection to the front of the frame to urge the fasteners forwardly in the magazine.

16. A pneumatic driver for driven type fasteners, comprising: a frame having a generally straight magazine for the fasteners and a barrel portion at one end thereof for receiving fastener driving mechanism; a guide plate member at the front of said magazine and having a slot therein to receive and position a fastener delivered thereto from the magazine for driving; a sleeve embracing the guide plate member and adjacent frame portion for holding the guide plate member in said fastener receiving position; and a foot member slidably mounted on said sleeve and having a lower work engaging surface for positioning the driver relative to work intended to receive the fastener driven therein.

17. A pneumatic driver as specified in claim 16 wherein said sleeve is slidably removable longitudinally thereof to release said embrace of the guide plate member to said frame, said sleeve and frame having cross bores positioned in alignment when properly assembled and a pin receivable removably in said cross bores to retain the sleeve, frame and guide plate member assembled.

18. A pneumatic driver as specified in claim 16 wherein the foot member comprises a split sleeve base telescoped over said embracing sleeve and a pair of side spaced plates secured on either side of the fastener driving position, said side plates having said lower work engaging surface.

19. A pneumatic driver as specified in claim 18 wherein said frame carries an air valve operating trigger above the magazine and a member connects said trigger with said foot member split sleeve for movement together relative to said frame permitting operation of the trigger upon relative movement of said frame and foot member upon the latter contacting said work to receive the fastener.

20. A pneumatic driver for driven type fasteners, comprising: a frame having a generally straight magazine for the fasteners and a barrel portion at one end thereof, a fastener driving mechanism in said barrel portion; a guide plate member at the front of said magazine and having a slot therein to receive and position a fastener delivered thereto from the magazine for driving; a sleeve embracing the guide plate member and adjacent frame portion for holding the guide plate member in said fastencr receiving position; a foot member having a split sleeve portion slidable longitudinally of said embracing sleeve and outer side plates attached thereto for engaging work to receive a driven fastener; pin members impaling said embracing sleeve, foot member and driver frame to retain assembly thereof, said foot member having elongated slots about said pins permitting longitudinal limited movement of the foot member relative to said frame; and air control means for said driving mechanism operatively connected to said foot member for actuation by said limited movement of the frame relative to the foot member.

21. A pneumatic driver as specified in claim 20 wherein said air control means includes an air valve control member carried on said frame and a link to operate the valve upon relative movement between the foot member and said frame, said foot member extending outwardly of said frame in position to contact work to receive a fastener and to operate said valve upon further movement of the frame to rest upon the work.

22. A pneumatic driver as specified in claim 20 wherein said foot member has a pair of rearwardly extending ears one on each side of said magazine, said air control means includes a control valve, a control valve operator member yieldingly urged downwardly toward said magazine and a push link member held captive between said ears and valve operator member so that downward movement of said frame relative to the foot member may raise the valve operator member.

References Cited in the file of this patent UNITED STATES PATENTS 2,887,686 Wendel et a]. May 26, 1959 

